require 'active_support/core_ext/class/attribute'
require 'active_support/core_ext/string/inflections'
require 'active_support/core_ext/file'
require 'action_view/helpers/tag_helper'
module ActionView
module Helpers
module AssetTagHelper
class AssetIncludeTag
attr_reader :config, :asset_paths
class_attribute :expansions
def self.inherited(base)
base.expansions = { }
end
def initialize(config, asset_paths)
@config = config
@asset_paths = asset_paths
end
def asset_name
raise NotImplementedError
end
def extension
raise NotImplementedError
end
def custom_dir
raise NotImplementedError
end
def asset_tag(source, options)
raise NotImplementedError
end
def include_tag(*sources)
options = sources.extract_options!.stringify_keys
concat = options.delete("concat")
cache = concat || options.delete("cache")
recursive = options.delete("recursive")
if concat || (config.perform_caching && cache)
joined_name = (cache == true ? "all" : cache) + ".#{extension}"
joined_path = File.join((joined_name[/^#{File::SEPARATOR}/] ? config.assets_dir : custom_dir), joined_name)
unless config.perform_caching && File.exists?(joined_path)
write_asset_file_contents(joined_path, compute_paths(sources, recursive))
end
asset_tag(joined_name, options)
else
sources = expand_sources(sources, recursive)
ensure_sources!(sources) if cache
sources.collect { |source| asset_tag(source, options) }.join("\n").html_safe
end
end
private
def path_to_asset(source, include_host = true)
asset_paths.compute_public_path(source, asset_name.to_s.pluralize, extension, include_host)
end
def compute_paths(*args)
expand_sources(*args).collect { |source| asset_paths.compute_public_path(source, asset_name.pluralize, extension, false) }
end
def expand_sources(sources, recursive)
if sources.first == :all
collect_asset_files(custom_dir, ('**' if recursive), "*.#{extension}")
else
sources.collect do |source|
determine_source(source, expansions)
end.flatten
end
end
def ensure_sources!(sources)
sources.each do |source|
asset_file_path!(path_to_asset(source, false))
end
end
def collect_asset_files(*path)
dir = path.first
Dir[File.join(*path.compact)].collect do |file|
file[-(file.size - dir.size - 1)..-1].sub(/\.\w+$/, '')
end.sort
end
def determine_source(source, collection)
case source
when Symbol
collection[source] || raise(ArgumentError, "No expansion found for #{source.inspect}")
else
source
end
end
def join_asset_file_contents(paths)
paths.collect { |path| File.read(asset_file_path!(path, true)) }.join("\n\n")
end
def write_asset_file_contents(joined_asset_path, asset_paths)
FileUtils.mkdir_p(File.dirname(joined_asset_path))
File.atomic_write(joined_asset_path) { |cache| cache.write(join_asset_file_contents(asset_paths)) }
# Set mtime to the latest of the combined files to allow for
# consistent ETag without a shared filesystem.
mt = asset_paths.map { |p| File.mtime(asset_file_path(p)) }.max
File.utime(mt, mt, joined_asset_path)
end
def asset_file_path(path)
File.join(config.assets_dir, path.split('?').first)
end
def asset_file_path!(path, error_if_file_is_uri = false)
if asset_paths.is_uri?(path)
raise(Errno::ENOENT, "Asset file #{path} is uri and cannot be merged into single file") if error_if_file_is_uri
else
absolute_path = asset_file_path(path)
raise(Errno::ENOENT, "Asset file not found at '#{absolute_path}'" ) unless File.exist?(absolute_path)
return absolute_path
end
end
end
end
end
end